Researchers from FOM research institute AMOLF in the Netherlands have produced the first images of a cloud of heavy protein ions during deposition and ionization. The images, enabled by an innovative detector, have provided the researchers with an insight into how protein ions on tissue are formed. The research has been published online on 3 September 2013 as a Very Important Paper (VIP) in Angewandte Chemie.
To produce the images, researchers from the group of professor Ron Heeren combined the so-called Timepix detector with a mass spectrometer, conventional detectors struggle with demonstrating the presence of large intact proteins in biological samples.
The Timepix detector was developed for high-energy physics, so the AMOLF researchers first had to adapt it for protein analysis. They did this by removing a photon sensor and replacing it with a plate sensitive for charged particles such as ions. The Timepix detector chip consists of 262,144 individual pixels, each of which separately measures the mass and location of the protein ions. Consequently the detector does not make a single measurement but produces 262,144 spectra from a single desorption event. The information density therefore strongly increases.
Read more at: Phys.org